Sigenergy SigenStor and Solax Triple Power are two of the most popular battery storage systems YEERS installs across Yorkshire. Both are excellent — but they suit different households. This head-to-head covers capacity, backup capability, smart tariff integration, warranty, pricing, and real-world performance from our installations.
Capacity Options
Sigenergy SigenStor is a fully modular system. You start with a 5kWh base unit and add 5kWh modules up to 20kWh — all in a single enclosure. This makes it the best choice for households that want to start small and expand as their needs grow (for example, when adding an EV charger later). The modular architecture means you never overbuy on day one.
Solax Triple Power comes in fixed capacities of 6.3kWh, 9.5kWh, and 11.6kWh via stackable T-BAT HV modules paired with a Solax X1-Hybrid or X3-Hybrid inverter. It's a mature, well-proven system, but capacity expansion requires purchasing a complete additional module — slightly less flexible than Sigenergy's approach.
Whole-Home Backup Capability
This is where the two systems diverge most significantly. Sigenergy SigenStor supports full whole-home backup. When the grid fails, the SigenStor switches seamlessly to backup mode and can power your entire property — including high-draw appliances like electric showers, induction hobs, and EV chargers (subject to battery capacity). Switchover time is under 20 milliseconds, meaning most electronics don't notice the transition.
Solax offers EPS (Emergency Power Supply) mode, which is a partial-home backup circuit. It powers a dedicated sub-circuit of lower-draw appliances — lights, phone chargers, a fridge — but cannot typically power the whole house. For most households this is sufficient, but if whole-home resilience is a priority, Sigenergy has a clear advantage.
Smart Tariff Integration — Octopus Flux and Agile
Both systems integrate with Octopus Flux and Octopus Agile via API. Sigenergy's cloud platform has a direct Octopus Flux integration that automates charge/discharge scheduling based on half-hourly tariff prices — the battery charges overnight at cheap rates (often 7-12p/kWh on Agile) and exports or self-consumes during peak periods (up to 35p/kWh on Flux export). Solax uses the Solax Cloud API, which is similarly capable but requires slightly more manual configuration to set up the Octopus integration compared to Sigenergy's plug-and-play approach.
Warranty Comparison
- Sigenergy SigenStor: 10-year product warranty with a guaranteed capacity retention of 70% after 6,000 cycles.
- Solax Triple Power: 10-year product warranty with 80% capacity retention over the warranty period (approximately 6,000 cycles at standard usage).
Both warranties are broadly comparable. Solax's 80% retention figure is marginally stronger on paper, though real-world degradation in Yorkshire's temperate climate tends to be better than warranty minimums for both brands.
Installed Pricing
- Sigenergy SigenStor: Approximately £900/kWh installed, all-in including the gateway, wiring, and commissioning. A 10kWh system costs roughly £9,000 at 0% VAT.
- Solax Triple Power: Approximately £750/kWh installed for the battery modules and X-Hybrid inverter package. A 9.5kWh system costs roughly £7,100 at 0% VAT.
Solax is the more affordable option per kWh. Sigenergy commands a premium for its modular architecture and superior backup capability.
Real-World Performance from Yorkshire Installations
Across YEERS installations in Hull, York, Selby, and Beverley, both systems perform well in the Yorkshire climate. Average annual round-trip efficiency is 92-94% for Sigenergy and 90-93% for Solax. In monitored installations paired with Octopus Agile, customers with a 10kWh Sigenergy system are saving an average of £820/year versus grid import, while Solax 9.5kWh customers average £690/year — reflecting both the capacity and the superior tariff-optimisation of the Sigenergy platform.
Our Verdict
Choose Sigenergy SigenStor if you want whole-home backup capability, plan to expand capacity in future, or have an EV and want seamless integration with Octopus smart tariffs. Choose Solax Triple Power if you want a proven, cost-effective system and partial backup is sufficient for your needs. Both come with YEERS' full installation warranty and commissioning support.
